Here is the full list of all 11 Enigmatis: The Ghosts of Maple Creek achievements worth 1,000 gamerscore.
Finished all Hidden Object Puzzles without using hints.
Finished the bonus chapter.
Finished game on normal difficulty
Finished Hidden Object Puzzle in less than 1 minute.
Found 3 hidden-objects within 3 seconds.
Finished 7 Hidden Object Puzzles in a row without using hints.
Finished 6 Mini-Games in a row without skipping.
Finished Mini-Game in less than 1 minute.
Finished Hidden Object Puzzle with less than 4 mistakes.
Finish all Mini-Games without skipping.
Finish game on expert difficulty